Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Quantas partes são nomeadas como Centro Aliança
 ###Tabelas: CREATE TABLE non-parliamentary_parties (non-parliamentary_parties_id AUTO_INCREMENT PRIMARY KEY, English party name VARCHAR, Norwegian party name VARCHAR, Associated ideology VARCHAR, Current leader VARCHAR, International affiliation VARCHAR, 2013 Parliamentary election VARCHAR, County councils ( 2011 ) INT) CREATE TABLE since_1963 (since_1963_id AUTO_INCREMENT PRIMARY KEY, Season VARCHAR, Division VARCHAR, Rank VARCHAR, Avg.Att. VARCHAR, Europe VARCHAR, Top Goalscorer VARCHAR, Goals INT) CREATE TABLE the_field (the_field_id AUTO_INCREMENT PRIMARY KEY, Post INT, Horse name VARCHAR, Trainer VARCHAR, Jockey VARCHAR, Opening Odds VARCHAR, Starting Odds VARCHAR, Finishing Pos. INT) CREATE TABLE slovenian_open (slovenian_open_id AUTO_INCREMENT PRIMARY KEY, Year Location VARCHAR, Mens Singles VARCHAR, Womens Singles VARCHAR, Mens Doubles VARCHAR, Womens Doubles VARCHAR) CREATE TABLE dry_measures (dry_measures_id AUTO_INCREMENT PRIMARY KEY, Unit VARCHAR, Russian VARCHAR, Translation VARCHAR, Ratio VARCHAR, Cubic inches (exact) VARCHAR, Metric value VARCHAR, Imperial value VARCHAR, US Customary VARCHAR)  
SELECT COUNT 2013 Parliamentary election FROM non-parliamentary_parties WHERE English party name = Center Alliance